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electrical gremlins

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Your wiring diagram should be right about the wiper motor wiring. Also, if I understood you right, the fuel gauge is still wrong. There should never be a brown/yellow wire there. Instead, it goes between the D post on the regulator and the D post on the generator. There should also never be a white wire there. Also, the only wires ever connected to that thumb screw terminal on the fuel gauge must be black grounds. That contacts both the gauge case and the back of the dash. Any violation of any of these will surely burn something down.

Please do yourself a really big favor. Disconnect everything first and follow my first suggestion. Using your ohmmeter, check all wires in the harness for continuity from end to end and put a tape lable on each end of each wire. If you are not sure of the purpose just put matching numbers on both ends. This will be a great help later Also check for any internal shorts between wires within the same bundle. Make any corrections necessary or tape new wires to the outside if you can't correct otherwise. Then add circuits back, one at a time, following the diagram explicitly and ignoring how it was connected before, checking each one for end to end continuity as well as for unintended shorts to ground. When that all checks out, it is safe to apply the voltage for testing. Only when that circuit is complete and tested should you go on to the next. You will note that some circuits will depend on others being installed first. For example, the white wire from ignition to the fuse must be made before any of the green circuits will work. The regulator is required for the ignition, etc.

Do not continue using that 30 amp breaker. Remember none of these circuits, with the possible exception of the horn, consume more that 8 or 10 amps at the very outside. Actually, if you check each one for shorts and find none then the big breaker is all right. For that matter, you shouldn't blow any more fuses either. But let's be safe here. Use a small 10 amp fuse and be ready to cut the power at the first sign of overload, whether the fuse blose or not.
 
I'm not anywhere near my wiring diagram - but, I managed to literally melt my hazard switch with excess current. turns out there are two identical harness plugs under the dash at the steering wheel and I had them backwards. At the very least, isolate each wire end and from each other so that you don't accidently short or ground
 
Okay, progress this time. Made new green off fuse block to behind dash the to blower/fuel gauge/wiper. Did not connect fuel or wiper end as not positive which spade gets which wire. Put in 30amp fuse. Connected ground to battery. Switched ignition on. The fire department did save most of the house.....kidding.
Fuse no blow. Only device hooked up that I'm fairly confident in was blower, pulled switch and she started up. So, likely I had the green and ground connected on either the fuel gauge or the wiper and thus shorted it. Now I just need to confirm the hookups of both those guys and I should be back to good. Then on to why the heck I lost all headlight function.....
 
Bayless said:
Your wiring diagram should be right about the wiper motor wiring. Also, if I understood you right, the fuel gauge is still wrong. There should never be a brown/yellow wire there. Instead, it goes between the D post on the regulator and the D post on the generator. There should also never be a white wire there. Also, the only wires ever connected to that thumb screw terminal on the fuel gauge must be black grounds. That contacts both the gauge case and the back of the dash. Any violation of any of these will surely burn something down.
Click to expand...

The brown/yellow and white on the fuel gauge are from the ignition warning lamp that I stole off the old harness, that white is really a red/white for hot from dash light switch and the brown yellow is ground, just for the bulb holder. I ran it to the thumb screw, then ran another jumper to the tach and speedo and so forth, have redundant grounds everywhere, especially since the dash is wood therefore of no help grounding. So, yeah ignore those, the light works fine. Sorry about the confusion on that.
 
NO NO NO, .. use a 5 or 10 amp circuit breaker... #14 wire is only good to 15 amps. those Lucas 35 amps fuses are really 17 amps
 
Okay, learned lesson on circuit breaker amperage the hard way, in my defense, it "felt wrong" to "allow" 30 amps through that wiring but I did it anyway (trust your gut)
I think I have figured out the original problem.
Wiring diagram shows the contacts on the wiper motor as E 1 2, I have found (only because I took a high res picture of it and someone at another forum pointed it out) that indeed the terminals on the wiper motor ARE labeled, only it goes E 2 1. Top to bottom, or E=earth (E, black), 2=hot (Green) 1=G/B hot/earth from switch.
I had the G and GB backwards (going by the diagram, which I'm finding out is NOT a reference for physical location of anything) essentially grounding the switched fused hot (G), popping the fuse, then when I disconnected some wires and used the totally wrong amperage circuit breaker, instead of bunch of wires absorbing the amps, it went through one and burned it up.
Now I will attempt to determine the correct G G/B B on the fuel gauge.
wipermotorbig.JPG
 
You're right on the brown/yellow wire being for the ign warning light. But it should connect between the actual light and the D post of the regulator. The other side of that light connects to a white wire from the ignition switch. The red/white is for the instrument light and connects between that light and the panel light switch. Neither should be connected to the fuel gauge ground terminal.

The two spades connected together on the fuel gauge should have a green wire. The green/black connects to the single spade. The thumb screw is its ground and gets a black wire. If you are concerned about that, check it with your ohmmeter like I described earlier. Check the resistance between each terminal and the case. The one with lower resistance is the green wire and the other is green/black.

I don't have that actual motor but it is a pretty simple single speed device. Looking at the diagram though, it appears that connecting green to #1 with black to E could in fact cause a direct short to ground.
 
Got lots of things sorted today. Thanks everyone. Fuel gauge doesn't want to work though. Maybe I fried it? The needle jumps as I turn the key on, then goes to E. (tank is full).
Blower works, wipers work, fuses don't blow, fuel pump was rewired and works, got the headlights (low beam only) to work. Got my horn push to work.....many steps forward today. Might even get her roadworthy in a week or two.
 
Wonderful!. Congratulations, it's great to hear of PROGRESS! Did you connect the fuel gauge like I suggested? I'm pretty sure now that is correct. I'd about bet a week's pay on it even. (Well, being retired, I guess that's not much of a bet). If so then I would disconnect the wires again and do the ohmmeter test.

OMG, I told you wrong before. From T to the case should be about 100 as I said but from B to the case should be more like 160. From B to T should be about 60. Man, now I really feel stupid now, as many cars as I have wired to make that mistake. Maybe I need to quit giving advice before someone gets hurt. Anyway, if you connected it based on the lower ohm reading as I suggested earlier, it is probably just backwards. I'm still convinced that the green wire goes to one of the double spades and the green/black to the other.

If you get about 160 from the E side post to the case, 100 from the F side to the case and about 60 between the spade posts then I'd bet the gauge is still good.
 
Since I found the B and T on the case the guess work is gone pretty much but it doesn't want to work, I probably had it shorted at some point and fried it.
 
Check those resistances.
 
Okay, I'll check them, I did swap the GB and the G and it registers 1/2 tank, (although should be full, I parked it full I swear..) goes to E with key off so maybe it just needed the swap over for neg earth conversion?

In other news, I managed to get a ride in yesterday!!!
Electrical issues are mostly sorted.
Remaining issues:
Somehow I lost dipswitch function so I only get one output at the switch the other won't energize (this is a non OEM switch that I put in last year after I found the original completely fried) I'll have to disassemble and investigate

Parking light: parking light on passenger's front won't light. I should disassemble and check the ground that I assume is at the housing. This side looks OEM, the other was rewired with different housing and wires.

Ammeter: this was registering 0 and looking fine but after running the car I found the needle pegged way to the plus side and it won't budge despite taking it completely out of the car and playing with it, hooking up the other way...something caused it to spike and I think the needle got physically stuck on the side of the case. Doesn't look like you can take these apart. I ordered a cheap voltmeter to put in that spot and I'll just connect those leads together or rewire to run right from solenoid to control box like OEM.

Ignition warning doesn't seem to work (never did before either) I sorta hoped it would after I set everything to OEM again but, oh well. Do I need to care?
 
No, the fuel gauge doesn't care about polarity. It will read the same whether you pos or neg ground. I'm still convinced that the green wire goes to the double post on the empty side and the green/black on the full side. If you have it connected that way and it reads empty with the ignition on then I would suspect a short to ground between the gauge and the sender. IF the needle is pegged with key off and moves to E when on then that is almost surely the problem or the sender is stuck. Remove the green/black wire from the gauge and check its ohms to ground. If zero or a very small number then that is the problem.

If that is a Smiths ammeter then you can open it up. Look on the back side of the bezel and you will see some tabs that hold it to the case. You can twist the bezel so that those tabs line up with notches in the case and it will lift right off. Before doing that, you might try just tapping on the side of the case to free up whatever is holding the needle though. If you replace it with a volt meter, it will connect entirely different than the ammeter does. Do not use those same wires.

Although you don't absolutely need that ignition warning lightas long as you have a gauge, it is nice to have. It really is a bettery discharge warning light. It lights when the generator output is lower than the battery. Its white wire goes to the switched post of the ignition switch with the other white wires. Its brown/yellow wire goes to the D post of the regulator. If connected this way and it does not light when you turn the key on then either the bulb is burned out or one of those wires is broken or not connected right.
 
Don't you need that light in the circuit somewhere as a load to tell the generator to turn on and start charging or something. Something in the back of my brain is telling me that needs to stay in the circuit for some reason. Tell me I'm wrong folks if I am.
 
I will do the ohm test on the fuel guage and report back. It seems to work hooked up "backward" (G to T and G/B to B instead of G to B and G/B to T)

Ignition light: I remember that too (you need it) from a thread a while back. I've always had a bulb in there but never noticed it light up. It's wired correctly. I haven't played with it much yet either though.

Felt really good to fire it up and drive. No hood and no insurance but went up the street anyway.

I need to ditch the Monza exhaust that is on there, am going to try a Harley pipe, it's too loud as is. It's not an "in your face" type car and that exhaust doesn't match, I need a more refined sound.
 
I don't think so Jim. If that were the case then when the bulb burned out you'd never know that your generator was not charging. Besides, my Prefect has the same generator and regulator and is wired the same except it does not have the warning light at all, just the ammeter and it works fine. The light effectively connects between the D post of the generator and the ungrounded battery post. As such, all it is doing is measuring the voltage difference between the two. When the generator is charging as much as the circuits require, it and the battery, through other wires, will be at the same voltage and the light goes out. When the generator voltage drops below the battery then it lights as a warning. That's all it does.
 
Bayless said:
OMG, I told you wrong before. From T to the case should be about 100 as I said but from B to the case should be more like 160. From B to T should be about 60. Man, now I really feel stupid now, as many cars as I have wired to make that mistake. Maybe I need to quit giving advice before someone gets hurt. Anyway, if you connected it based on the lower ohm reading as I suggested earlier, it is probably just backwards. I'm still convinced that the green wire goes to one of the double spades and the green/black to the other.

If you get about 160 from the E side post to the case, 100 from the F side to the case and about 60 between the spade posts then I'd bet the gauge is still good.
Click to expand...

T to (ground, case, earth)=96
B to (ground, case, earth)=153 but swings around pretty crazy and "settles" briefly at either 150ish or upper 80s.
B to T =58
Now the weird part. hooked it up turned on key, needle flickers and goes to E. Pull off GB from the T terminal, put it back on, gauge reads 1/2. Poor connections or flaky ground? Is there a way to check the sender or is that all in the tank?
 
Bayless said:
When the generator voltage drops below the battery then it lights as a warning. That's all it does.
Click to expand...
It works in the other direction too; it will indicate an overcharge <span style="font-style: italic">or </span>an undercharge. So it'll detect a bad batt as well as a bad alt. Neat design. It's an electrical tug-o-war!
 
:iagree: What I was talking about was a more normal situation with components functioning reasonably right. True enough in the event of a catastrophic component failure (battery or regulator) but not under normal or usual circumstances.
 
Gremlins are all banished (for the moment).
Ignition light works as intended.
Headlights were intermittent to a break in one of the ground wires.
Parking light was resurrected by fiddling around (probably restoring a decent ground connection in the process).
Everything is fused as it should (add on components, fuel pump, radio, relays all have their own separate fuses as well).
Only issue is the high beam indicator doesn't want to light but I'm sure that's simple too.
Hope to drive it this afternoon!!
 
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